This invention relates to bar locks of the type used to lock doors and other access panels on trailers, containers and the like, and to an improved method for assembling such bar locks.
Bar locks are in widespread use as closures for doors on semi-trailers, containers and the like. Cerutti U.S. Pat. No. 3,912,312 discloses one prior art bar lock which utilizes upper and lower latching elements that are individually journaled by bearings mounted by bolts onto the door or other movable panel. The journaled latching elements are rotated by an operating bar, and are welded to respective ends of the operating bar. A handle is secured to an intermediate portion of the operating bar to rotate the bar, and therefore the latching elements.
Prior art bar locks of the type disclosed in the Cerutti patent can be relatively cumbersome to install on the trailer or container. The bar lock is made up of a relatively large number of parts which must be separately handled and assembled by the installer. Furthermore, the upper and lower latching elements are welded to the operating bar. If these welds are made at the time of final assembly, there may be a need to regalvanize the operating bar to reduce corrosion. Alternately the latching elements and the operating bar may be welded together by the manufacturer. In this case, the fully assembled unit as shipped by the manufacturer is not well suited for modification to differing height doors. Furthermore, the fully assembled unit has a considerable length which makes it cumbersome and expensive to ship.
Bartsch U.S. Pat. No. 1,952,112 describes another type of bar lock in which the operating bar is square in section and is designed to fit into sockets formed by the upper and lower latch members. This approach allows the length of the operating bar to be adapted at the time of assembly to fit the particular application. However, the Bartsch bar lock is still formed of a unnecessarily large number of components which must be handled as separate units and assembled at the time the bar lock is installed on the trailer.
Pelson U.S. Pat. No. 4,127,291 discloses another bar lock in which one of the latching elements is welded in place to the operating bar, while the other is held in place by a bolt passing through a diametrically disposed hole in the bar. Once again, the bar lock of the Pelson patent is not well adapted for rapid installation.
Accordingly, it is an object of this invention to provide an improved bar lock and method for assembly that minimize the time required to install the bar lock on the trailer or other container.
It is another object of this invention to provide bar lock modules which can be shipped as preassembled units which are compact and relatively inexpensive to ship, and which can be easily and quickly assembled with other components at the time the bar lock is installed on the trailer or the container.